Measuring and centering device



May 4 1926. v

. E. A.EMERY MEASURING AND CENTERING DEVICE Filed April 18, 1924 measuring inside diameters of cylinders of Patented May 4, 1926.

EDGAR TAQEMVERY, or SAN, ANTONIO, TEXAS.

MEASURING AND OENTERING DEVICE.

Application filed April 18, 1924. SeriaINo. 707,383.

To all whom it may concern:

Be-it known that I, EDGAR A. EMERY, citizen of the United States, residing at San Antonio, 'in' the county of Bexar and State of Texas,.have invented certain new and useful Improvements in Measuring and ularlyto an apparatus for measuring inside Centering Devices, of which the following is a specification.

'This invention relates in general to measuring and centerlng devices and more partlcdiameters of cylinders and the like and determining the centering line of the bore thereof." i

In the construction, assembly and repair of locomotives, it is essential to the-successful operation of'thelocomotive that the guides on the cylinder shall be accurately aligned and equidistantly spaced from the center line of the bore of the cylinder. Here- I tofore a very crude and ineificient method of determining the center line has been employed. It'has been the practice to remove the cylinder heads, drive a block of wood into each end of the cylinder, determine the centers of the blocks of wood by the use of calipers, bore a hole at the center thus found,

' secure to the block a metal plate having an aperture coinciding withthat'bored into the block, and, then stretch a cord or wire through these apertures. This wire is thenassumed to represent a true center line of the bore of the cylinder. Obviously such a crude method ofdetermining this line is inefficient, wasteful of material and time and 1 in addition gives inaccurate results.

It is an object of my invention to provide a novel'and improved device. for measuring inside diameters and on'e'which is capable ofseveral adjustments to permit its. use in many different sizes. It is a further and most important object of myvinvention to provide a device by the use of which, either automatically .or by ready and simple; ad-

Figure 2 is a detail in vertical section showing the interior er of Figure 1.

Figure 3 is an end of Figure 1.

Figure 4 is a detailview of aportion'v of my device. 7

structure ofthe plungview ofthe member9 Figure 5 is a detail side elevation of i a portion of my device' Figure 6 is a detail of a;portion of the device shown in Figure 5; i I

Referring with greater particularity. to

the drawings, it will beseen that my device is comprised as follows: 1', i

The main body. member 1 of my device has a central cross-bored portion 2 and oppositely extending arms 3' and 4, :The'arms 3 and 4: with theirvariousscomp'onent parts are identicalin structure and therefore but one will be described in detail." The arm?) hasa central bore 5 extending longitudinally thereof adapted to receive and: to allow for the reclprocationpof'a plunger 6 having a shoulder 7 adapted to have a sliding fit with theinterior of the-bore 5. i A suitable'compression spring 8 has one seatv in the'base ofthe bore 5 and is adapted-to surround the lower endof'the plunger 6 and bear against the'inner face of the shoulder 7 The outer end of the arm 3 is provided, with internal screw threads and is adaptedto receive the threaded gland 9 which acts as a retaining means for the plunger 6. The threaded gland 9 has a square cut aperture 10 in which the plunger 6bears. A set screw 11 extends laterally through the head of the gland 9 andis adapted to bear against the square face of the plungerfito' hold-it in any desiredg'position with relation tothe gland.- "The graduated scale'12is formed integrally with or secured in any suitable manner to one side of the plunger 6. 1 The plunger 6 is provided withan internal screw threaded shank -14; of a rod 16. The rod 16 terminates in aball shapedhead-17 andis provided along its shank 14 ;,with -a suitable graduated scale 18; v

A member 20 having an incut portion 21 and knurled grip 19 is adapted to be fitted within the transverse bore 2, to which it is secured by plates 22 and screws 23, the plates '22 fitting the member 20 at its incut portion threaded; bore 13 adapted to receive the 21. I The member 20 is provided with a longitudinally extending screw threaded bore 24, which is adapted to receive the externally screw threaded sleeve rod 25. This member 25, adjacent to one end thereof is bored as shown at 26, the outlet 27 of the bore 26 being at the center of the end of the member 25 and the outlet 28 terminating in the side thereof.

lVIy device having been described in as tail its operation willbe seen to be as follows: v

When it is desired to measure the inside diameter of any cylinder or the like the plungers 6 are pressed inwardly against the action of their springs 8 and held in this position by means of the set screws 11. When the instrument is placed within the interior of the cylinder, the set screws are loosened, the springs then forcing the plungers 6 outwardly until the balls 17 contact with the cylinderwalls, which on account of their spherical shape, automatically seek the greatest position of extension which will be that of the diameter of the circle of the cylinder. This diameter can then be read directly on the graduated scales. When the set screws 11 are released the two plungers 6 will be pressed outwardly to the same degree if the springs 8 .are equal in force. If the two scales12are pushed outwardly to the same extent, as can be noted from the scales 12, the port 27 willbe in exactly the center of the bore of the cylinder. If, however, the springs are of unequal strength and one plunger is pressed outwardly to a slightly greater extent thanthe other, it is only necessary to press the instrument downwardly against the action of the stronger spring until the two scales show the same reading. The set screw 11 adjacent the plunger actuated by the stronger spring is then tightened against the side of this plunger and the bore 27 thus held in the exact center of the cylinder. The other set screw ll'may then be tightened. I

When it is desired to determine the center line of the bore of the cylinder, two of the devices such as I have illustrated, are used, one on each end of the cylinder. The center of each end of the bore of the cylinder is member 20 and thus tighten the cord or wire and determine the central line of the bore of the cylinder.

It will be noted that this device may be adjusted to measure larger diameters by adjusting the rods 16 in the bores 13.

I' claim:

1. In combination, in a device of the character described, a body portion, oppositely extending spring-pressed plungers carried by said body portion, said body portion having a centrally disposed transverse centering screw threaded boreand a screw threaded rod longitudinally adjustable in said bore.

2. In a device of the character described, in combination, a body portionhavingoppositely extending arms. and a central portion provided with a transverse centering bore, said arms having bores extending longitudinally thereof, spring pressed plungers slidably mounted in said bores, andv a rod carried by and longitudinally adjustable in said transverse bore. I

3. In a device of the character described, in combination, a body portion having oppositely extending arms. and a central pori tion provided with a transverse centering bore, said arms having bores extending longitudinally thereof, spring-pressed plungers slidably mounted in said bores, a rod carried by and longitudinally adjustable in said transverse bore there being scales on said plunger.

4. In a device of'the character described, in combination, a body portion having oppositely extending arms and a central portion provided with a transverse centering bore, said arms having bores extending longitudinally thereof, spring 7 pressed plungers slidably mounted in said-bores, a rod carried by and longitudinally adjustable in said transverse bore, said plungers having scales thereon and being adjustable in length.

5. In combination, in a device of the character described, a body portion having oppositely extending arms and avcentrally disposed transverse bore, said arms being provided with bores extendingv longitudinally thereof, oppositely extending spring pressed plungers mounted in saidlongitudinal bores in said body portion and adapted to center said transverse centering bore in thecylinder in connection with which the device is to be used and means for fixing said plungers in any position to which they. are adjusted.

In testimony whereof I. afiix my signature. EDGAR A. 

